condition mean min max ZT0-3 12.059018333333334 8.259855 15.3202 ZT4-7 6.263865 6.263865 6.263865 ZT8-11 4.57445 4.57445 4.57445 ZT12-15 4.9059275 4.69347 5.118385 ZT16-19 4.549665 4.549665 4.549665 ZT20-23 8.49716 8.49716 8.49716